This invention relates to siding panel systems and methods of installing them on a wall or the like, and more particularly to systems and methods for mounting a horizontal siding panel between and in lapped relation to vertically spaced upper and lower courses of such panels already mounted on a wall. In an important specific aspect, the invention is directed to methods and systems for mounting a horizontal siding panel at the joint between upper and lower panel-clad prefabricated wall sections.
Horizontally elongated siding panels made of roll-formed sheet metal or molded plastic are widely employed for cladding exterior building walls. Typically, they are mounted in parallel, overlapping, interlocked relation on a wall with their surfaces sloping downwardly and outwardly to simulate the appearance of wooden clapboards or rows of shingles. Each panel is attached at its top margin to the wall by suitable fasteners, such as nails driven through a flat nailing flange portion of the panel top margin. A first locking means (e.g. an outwardly projecting lip) is formed on each panel adjacent the top margin and below the nailing flange; a second locking means (e.g. an inwardly projecting, upwardly opening channel flange), formed at the bottom margin of each panel, overlies and interlocks with the first locking means or lip of the next lower panel on the wall to secure the panel bottom margin to the wall and to conceal the fasteners that hold the lower panel.
In conventional installation of such panels, the bottom flanges of the panels of the lowermost course to be installed on a wall are first interlocked with a starter strip previously mounted along the lower edge of the wall, and the top margins of these lowermost panels are nailed to the wall. The bottom flanges of the panels of the second (next higher) course are then interlocked with the lips of the panels of the lowest course, and the top margins of the second-course panels are nailed to the wall. Thereafter, progressively higher courses of the panels are installed in succession in like manner one above another, until the wall is fully clad with a continuous array of the panels, each held along its top margin by nails and along its bottom margin by interlocking engagement with the adjacent lower course of panels so as to be fully secured against dislodgement.
It would sometimes be desirable to interpose a panel or a course of panels in a gap or space between previously installed upper and lower courses, i.e. at a location which is below as well as above already-mounted courses of panels. Unless the already mounted upper and lower courses are precisely spaced a proper distance apart, however, it is not possible to interlock both the first and second locking means of the interposed panel with the second locking means of the upper panel and the first locking means of the lower panel, respectively, because the tolerances for such spacing (to achieve the requisite interlocking at both the top and bottom of the interposed panel) are very small. Attainment of requisitely precise spacing is extremely difficult. In addition, since for proper overlapping and interlocking the top margin of the interposed panel must be inserted behind the bottom margin of the already-mounted upper panel, it is in general virtually impossible to fasten the top margin of the interposed panel to the wall, as necessary to secure both the interposed panel and the bottom margin of the upper panel. Consequently, the secure and stable installation of a panel interposed between vertically spaced courses of already-mounted panels has heretofore presented serious problems.
One commercially important situation in which the foregoing problems arise is in the use of siding panels on prefabricated buildings, wherein exterior walls (e.g. frame walls constituted of wooden studs, and having sheathing, doors, windows, etc.) as well as other components are produced in a more or less finished condition by a manufacturer and transported to a construction site for assembly. Since it is frequently difficult or impossible to transport a building wall (especially a wall more than one story high) as a single integral unit, prefabricatd exterior walls are commonly made in two or more sections which are assembled one above another at the construction site. Installation of siding panels on prefabricated walls by the manufacturer is often considered desirable, to reduce labor costs in the field, to control the amount of siding used, and to expedite final assembly of the building; but in the case of walls prefabricated in upper and lower sections having siding panels installed by the manufacturer, there is a discontinuity on the assembled wall between the arrays of panels respectively mounted on the upper and lower wall sections.
That is to say, it is not feasible to dispose the top course of panels on the lower wall section and the bottom course of panels on the upper wall section so that they will interlock properly, or to effect such interlocking when the sections are assembled. Ordinarily, then, it is necessary to leave a gap (i.e. at the juncture of the wall sections) between the upper and lower panel arrays; and indeed, since the height of the lower wall section is usually not equal to the height of an intergral number of courses of siding panels, such a gap is practically unavoidable. In such instances, it would be extremely difficult to so locate a bottom course of panels on the upper wall section that the height of this gap will equal the height of one course of panels, within proper dimensional tolerances for conventionally interlocking a course of panels between the upper and lower arrays. Moreover, even if the panels could be so disposed, it would not be feasible to properly secure the top margin of the course of panels thus interposed between the arrays.
For these reasons, in assembling upper and lower prefabricated wall sections having pre-installed siding panels, resort has heretofore been had to makeshift expedients such as the use of wooden trim boards to bridge the gap between the arrays of siding on the respective sections. These expedients are unsatisfactory both from the standpoint of appearance and because they detract from the protection and durability afforded by a continuous interlocked array of siding panels of the described type.